# Custom formula to calculate the total cost of items with coupon discounts

In this example, we’ll create a custom formula that calculates the total cost of items in a shopping cart, considering discounts based on a coupon code.

Scenario: You want to create a custom formula that calculates the total cost of items in a shopping cart, taking into account discounts based on a coupon code.

We’re diving into the world of cost calculations, discounts, and coupon codes using Google Apps Script. 📈

Introducing the “COST_PER_ITEM” function, a handy tool that allows you to effortlessly determine the cost of an item based on its quantity, price, and even the potential discounts from coupon codes. Whether you’re a business owner optimizing your e-commerce site or a developer looking to streamline your financial calculations, this function can be a game-changer.

Here’s what you’ll discover in this video:

How to use the “COST_PER_ITEM” function effectively.

Understanding the role of parameters like quantity, price, and coupon codes.

The importance of the “discountTable” and how it drives cost reductions.

A closer look at the “getDiscount” function to find applicable discounts.

Plus, we’ll walk you through practical examples and real-world applications to illustrate how this script can simplify cost calculations in various contexts.

Don’t miss out on this opportunity to enhance your financial modeling and streamline cost management. Join us in the video to unlock the full potential of these functions.

=COST_PER_ITEM( A2,B2,C2,D2,G2:H4)

function COST_PER_ITEM(item,quantity,price,couponCode,discountTable){

const discount = getDiscount(couponCode,discountTable);

let cost = quantity * price;

cost = cost – (cost * discount);

return cost;

}

function getDiscount(couponCode,discountTable){

for(let i=0;i<discountTable.length;i++){

if(discountTable[i]===couponCode){

return discountTable[i];

}

}

return 0;

}

The provided Google Apps Script code contains two functions: COST_PER_ITEM and getDiscount. These functions work together to calculate the cost of an item based on its quantity, price, and an optional coupon code that may offer a discount. Here’s a detailed description of how these functions work:

1. COST_PER_ITEM(item, quantity, price, couponCode, discountTable) Function:

This function calculates the cost of an item, taking into account its quantity, price, and any applicable discounts provided through a coupon code. Here’s a breakdown of its functionality:

• item: This parameter seems to be unused in the function, so it’s not impacting the calculation of the cost.
• quantity: The quantity of the item you want to purchase.
• price: The unit price of the item.
• couponCode: An optional parameter that represents a coupon code. If a valid coupon code is provided, the function checks for discounts in the discountTable.
• discountTable: An array that stores coupon codes and their corresponding discounts. The array is a two-dimensional array, where each sub-array contains a coupon code in the first element and the associated discount percentage in the second element.

The function proceeds as follows:

• It calls the getDiscount function to check if a valid discount is available for the given couponCode in the discountTable.
• The discount variable is assigned the discount percentage obtained from the getDiscount function.
• It calculates the initial cost of the items (quantity * price).
• The cost is adjusted by subtracting the discount percentage from it (cost – cost * discount). If no valid discount is available, the discount percentage is 0, so the cost remains unchanged.
• Finally, the function returns the calculated cost after taking any discounts into account.

2. getDiscount(couponCode, discountTable) Function:

This function is responsible for looking up the discount associated with a given couponCode in the discountTable. Here’s how it works:

• couponCode: The coupon code for which you want to find the discount.
• discountTable: The array that stores coupon codes and their corresponding discounts.

The function proceeds as follows:

• It iterates through the discountTable array using a for loop.
• For each entry in the discountTable, it checks if the coupon code provided as the argument matches the coupon code in the current entry (discountTable[i]).
• If a match is found, the function returns the discount percentage (discountTable[i]) associated with that coupon code.
• If no match is found after iterating through the entire discountTable, the function returns 0, indicating that there is no applicable discount for the provided coupon code.

These functions can be used to calculate the cost of items with discounts based on coupon codes, making them useful for various e-commerce and business scenarios where cost calculations need to consider discounts.

Title: “Unlocking Cost Optimization with Google Apps Script: A Comprehensive Guide”

In our latest video, we’re delving deep into the world of cost calculations, discounts, and the magic of Google Apps Script. Whether you’re a business owner striving to fine-tune your e-commerce platform or a developer seeking to streamline financial computations, this video is for you.

🔹 The “COST_PER_ITEM” function: How to utilize it effectively.

🔹 An in-depth look at key parameters like quantity, price, and coupon codes.

🔹 The pivotal role of the “discountTable” in driving cost savings.

🔹 A detailed understanding of the “getDiscount” function for identifying discounts.

We’ll illustrate these concepts with real-world examples, making it easy to grasp the practical applications of this script in different scenarios.

Don’t miss out on this opportunity to elevate your financial modeling and make cost management a breeze. Join us in the video to harness the full potential of these functions.

Data Table:

Coupon Codes and Discounts:

Step 1: Setting up the Spreadsheet

• Create a new Google Sheets document.
• Enter your item details, quantities, prices, and coupon codes in columns A to D starting from row 2.
• Leave cells in columns E and F empty for now.
• Enter the coupon codes and their corresponding discounts in columns H and I.

Step 2: Writing the Google Apps Script Code

• Click on “Extensions” in the top menu, then select “Apps Script”.
• Delete any default code and replace it with the following script:

// Custom formula to calculate the total cost of items with coupon discounts

function CALC_TOTAL_COST(items, quantities, prices, couponCodes, discountTable) {

var totalCost = 0;

for (var i = 0; i < items.length; i++) {

var quantity = quantities[i];

var price = prices[i];

var couponCode = couponCodes[i];

var discount = getDiscount(couponCode, discountTable);

var cost = quantity * price;

cost = cost – (cost * discount);

totalCost += cost;

items[i] = cost;

}

}

// Helper function to get the discount from the discount table

function getDiscount(couponCode, discountTable) {

for (var i = 0; i < discountTable.length; i++) {

if (discountTable[i] === couponCode) {

return discountTable[i];

}

}

return 0; // Default to no discount if coupon code not found

}

Step 3: Using the Custom Formula in Google Sheets

• In cell F2, enter the following formula:

=CALC_TOTAL_COST(A2:A, B2:B, C2:C, D2:D, H2:I)

Explanation of the Code:

• The function CALC_TOTAL_COST calculates the total cost of items in a shopping cart, considering discounts based on a coupon code.
• It takes five parameters: items, quantities, prices, couponCodes, and discountTable.
• items: The range of cells containing the item names.
• quantities: The range of cells containing the quantities for each item.
• prices: The range of cells containing the prices for each item.
• couponCodes: The range of cells containing the coupon codes for each item.
• discountTable: The range of cells containing the coupon codes and their corresponding discounts.
• Inside the function, a loop iterates through each item in the shopping cart.
• It calculates the cost of each item and applies the discount based on the coupon code.
• The getDiscount helper function is used to retrieve the discount from the discount table based on the coupon code.
• The calculated cost of each item is stored in column F.
• The function returns the total cost of all items in the shopping cart.

Step 4: Testing the Custom Formula

• Enter item details, quantities, prices, and coupon codes in columns A to D starting from row 2.
• Enter the coupon codes and their corresponding discounts in columns H and I.
• Use the custom formula in cell F2 to calculate the total cost of items in the shopping cart with applicable discounts.

For example, if you have entered the item details and coupon codes as shown in the data table, the calculated total cost in cell F2 should reflect the cost of items with applicable discounts based on the coupon codes.

Remember to enable the “Google Apps Script” extension and use the exact function name (CALC_TOTAL_COST) in your formula.